High T/sub c/ SQUID system and magnetic marker for biological immunoassays
High T/sub c/ SQUID system and magnetic marker for biological immunoassays
复制标题
DOI：
10.1109/tasc.2003.813856
复制
发表时间：
2003-07
影响因子：
1.8
通讯作者：
K. Enpuku;Daisuke Kuroda;T. Yang;K. Yoshinaga
中科院分区：
文献类型：
--
作者：
K. Enpuku;Daisuke Kuroda;T. Yang;K. Yoshinaga
为了检测抗原与其抗体之间的生物结合反应，研制了高T/subc/SQUID系统。在这种测量中，抗体被标记上磁性纳米颗粒，并测量来自纳米颗粒的磁性信号。将几mT的激发场平行地施加到SQUID上，以使纳米粒子磁化。然而，由于机械失调，激励场的垂直分量耦合到SQUID，从而降低了系统的性能。为了解决这个问题，我们提出了两种方法。一种是在磁通坝的情况下使用补偿场，另一种是使用开关来代替磁通坝。我们还利用直径为25 nm的Fe/sub3/O/sub4/纳米粒子研制了一种磁性标记。纳米粒子包埋在典型的直径为80 nm的聚合物中，COOH附着在聚合物的表面。讨论了该标记的性质。
High T/sub c/ SQUID system is developed for the detection of the biological binding-reaction between antigen and its antibody. In this measurement, the antibody is labeled with magnetic nanoparticles, and the magnetic signal from the nanoparticles is measured. The excitation field of a few mT is applied in parallel to the SQUID in order to magnetize the nanoparticles. Due to mechanical misalignment, however, the vertical component of the excitation field couples to the SQUID, and degrades the system performance. In order to solve this problem, we develop two methods. One is the use of a compensation field in the case of the flux dam, and the other is the use of a switch instead of the flux dam. We also develop a magnetic marker utilizing Fe/sub 3/O/sub 4/ nanoparticle with diameter of d=25 nm. The nanoparticle is embedded in the polymer with typical diameter of 80 nm, and COOH is attached around the surface of the polymer. The properties of the marker are discussed.